Nacre-Inspired Aramid Paper With Boron Nitride Nanosheets Could Keep Overheating Electronics Cool

Engineers chasing faster processors, denser power electronics and brighter LED systems keep running into the same stubborn bottleneck: heat. As electrical devices pack more power into less space, the insulating materials that keep current safely contained also trap thermal energy, pushing components toward the temperatures that degrade performance and shorten lifetimes. A team of researchers in China now reports a materials solution that borrows its blueprint from an unlikely teacher — the inner surface of an abalone shell — and turns ordinary aramid paper into a thermally efficient, electrically insulating heat-spreading platform that could reshape how high-power electrical systems manage their own warmth.

Aramid paper, a fibrous mat built from aromatic polyamide (PMIA) fibers, has long been prized in motors, transformers and electrical insulation for its combination of mechanical strength, flexibility and dielectric reliability. Yet its intrinsic thermal conductivity is low, a limitation that becomes a liability in next-generation high-power electrical systems where waste heat must be drawn away quickly. The conventional fix — loading the paper with thermally conductive fillers — routinely backfires. Fillers clump together, resist bonding with the surrounding polymer, and in doing so weaken the very mechanical and electrical properties that make aramid paper attractive in the first place.

Writing in the journal Advanced Composites and Hybrid Materials, Wenqi Leng, Jinke Liu, Jinpeng Li, Yongfeng Li and Kefu Chen describe a strategy that sidesteps the agglomeration trap by engineering the interfaces within the material rather than simply stuffing it with filler. Their central move is to functionalize boron nitride nanosheets with hydroxyl groups, producing OH-BNNS whose surface chemistry is far more compatible with the aramid framework. These hydroxylated nanosheets are then assembled into a biomimetic, nacre-like architecture — a multilayered laminated structure echoing the brick-and-mortar arrangement that gives mother-of-pearl its legendary combination of hardness and toughness.

The composite paper, designated PPH@B, is genuinely multicomponent. OH-BNNS platelets are combined with PDOPA-modified PMIA chopped fibers — short aramid fibers whose surfaces have been coated with polydopamine, a mussel-inspired adhesive polymer — alongside unmodified PMIA floc fibers and hydroxyapatite nanowires. A second variant, PPH@MB, adds mica nanosheets to the lamellar network, allowing the team to evaluate how additional insulating platelets influence the structure’s heat-transport behavior. The interfacial engineering improves the dispersion of the hydroxylated nanosheets and promotes close, intimate contact between the boron nitride platelets and the aramid-based scaffolding around them, supporting the formation of connected in-plane heat-transfer pathways that run parallel to the plane of the paper.

The resulting performance figures are striking for a flexible insulating paper. The optimized composition, PPH@B(20), achieves an in-plane thermal conductivity of 5.16 watts per meter-kelvin — a figure several times higher than that of conventional aramid paper, which typically struggles to move heat at all. Critically, this thermal upgrade does not come at the expense of the properties that matter for electrical insulation. The same material retains a tensile strength of 68.79 megapascals and an electrical breakdown strength of 35.45 kilovolts per millimeter, meaning it can still bear mechanical load and withstand intense electric fields without failing.

That balance — high thermal conductivity, strong mechanical integrity and robust dielectric behavior in a single flexible sheet — is the triad that has long eluded thermally conductive composite papers. Usually, pushing one property sacrifices another: more filler means better heat transport but weaker, more brittle paper with compromised insulation. The nacre-inspired lamellar design resolves this tension by creating ordered, overlapping networks of nanosheets and fibers, where heat glides along continuous boron nitride highways while the aramid fibers and hydroxyapatite nanowires act as reinforcing struts, and the modified interfaces keep everything bonded and evenly distributed.

The practical payoff was demonstrated in a real device context. When applied to LED devices, the PPH@B composite paper achieved a significant reduction in operating temperature, pulling heat away from the light-emitting junctions more effectively than standard insulating substrates. For LEDs, lower operating temperature translates directly into better luminous efficiency, slower color shift and longer service life — the kind of cumulative reliability gain that matters enormously in lighting, displays and automotive systems. The same heat-spreading logic applies to power modules, motor insulation and the growing class of advanced electronic packaging where insulating layers must double as thermal pathways.

The researchers also report that the composite exhibits excellent flexibility and dimensional stability, two qualities that are easy to overlook but essential for manufacturing. Insulating papers must be wound, cut, laminated and stacked without cracking, delaminating or warping, and they must hold their dimensions through thermal cycling in service. A heat-spreading material that curls, shrinks or fractures under handling would never leave the laboratory. The nacre-like layered structure, in which stiff platelets are interleaved with tougher fibrous phases, is precisely what gives natural mother-of-pearl its damage tolerance, and the same architectural principle appears to carry over to the synthetic paper.

Behind the headline numbers lies a broader lesson about bioinspired design. Rather than treating composite materials as random mixtures, the team treated them as architectures — carefully ordered assemblies in which each component’s shape, surface chemistry and placement is chosen to serve a specific function. Polydopamine modification of the chopped aramid fibers, hydroxylation of the boron nitride nanosheets, and the deliberate inclusion of nanowires and platelets of different aspect ratios together create a hierarchical material whose interfaces do the heavy lifting. It is a strategy that mirrors how nature builds strong, functional materials from humble ingredients, and it suggests a roadmap for the next generation of multifunctional papers and films.

The work was carried out at the Plant Fiber Material Science Research Center of the State Key Laboratory of Advanced Papermaking and Paper-based Materials at South China University of Technology, in collaboration with Guangdong Guanhao New Material R&D and Ganzhou Longpont Materials Technology, and was supported by funding from the Science and Technology Major Projects of Jiangxi Province, the National Natural Science Foundation of China, the State Key Laboratory of Advanced Papermaking and Paper-based Materials, and the Guangzhou Science and Technology Plan Project. The study was published open access on 19 September 2026, and the authors declare no competing interests. As power densities continue to climb across electric vehicles, renewable-energy converters and data-center hardware, a paper that insulates electricity while conducting heat — built on the engineering wisdom of an abalone shell — may prove to be exactly the quiet innovation that keeps the modern world from overheating.

Subject of Research: Nacre-inspired hydroxylated boron nitride nanosheet/aramid composite papers with interfacially engineered lamellar networks for efficient thermal conduction in electrical systems.

Article Title: Nacre-inspired hydroxylated BNNS/aramid composite paper with interfacially engineered lamellar networks for efficient thermal conduction

Article References: Leng, W., Liu, J., Li, J., Li, Y., & Chen, K. (2026). Nacre-inspired hydroxylated BNNS/aramid composite paper with interfacially engineered lamellar networks for efficient thermal conduction. Advanced Composites and Hybrid Materials. https://doi.org/10.1007/s42114-026-02057-2

Image Credits: AI Generated

DOI: 10.1007/s42114-026-02057-2

Keywords: boron nitride nanosheets, aramid paper, thermal conductivity, nacre-inspired materials, interfacial engineering, nanocomposites, electrical insulation, hydroxyapatite nanowires, thermal management, electronic packaging, bioinspired materials, polydopamine